Senior Senate Republicans remain noncommittal on the president’s anticipated nomination of Republican Chuck Hagel as his next secretary of defense, amid growing opposition from pro-Israel groups and commentators.

Several senators said Tuesday that the former Nebraska senator would face tough questions in a confirmation hearing on past statements about Israel and broader Middle East policy that critics say reflect an anti-Israel bias and a more hands-off approach to the Middle East than many hawks prefer.

Hagel, said Senate Armed Services Committee member Lindsey Graham, R-S.C., will “have to answer questions about why he thought it was a good idea to directly negotiate with Hamas and why he objected to the European Union declaring Hezbollah a terrorist organization.”

However, Graham said he would not oppose a Hagel nomination right out of the gate. “I want to listen to what he has to say because I like Chuck, he’s been a friend. He has a stellar military record,” said Graham. “But I think these comments disturb a lot of people and he’ll have to answer those questions.”

“A lot of times,” Graham added, “hearings are just for show.” But a Hagel nomination hearing “will really matter,” he said.

Many Republican senators were not willing to give the same benefit of the doubt to United Nations Ambassador Susan E. Rice, purportedly President Barack Obama’s favored candidate to replace outgoing Secretary of State Hillary Rodham Clinton. Graham and fellow Senate Armed Services Committee Republicans John McCain of Arizona and Kelly Ayotte of New Hampshire led the opposition to her nomination, citing statements she made in the wake of the attack on the U.S. consulate in Benghazi, Libya. Rice withdrew her name from consideration last week, citing “baseless political attacks.”

The same senators’ relative reticence on Hagel reflects a trickier set of political — and personal — dynamics at play.

Hagel, a Republican who represented Nebraska in the Senate from 1997 to 2009, served with many of the Republicans still in the chamber and has good relationships with many. Several Republicans noted that on Tuesday.

“Sen. Hagel is a friend of mine, he was a fine senator. I know him well from having served with him,” said Sen. Susan Collins, R-Maine, a member of the Senate Armed Services Committee, which would oversee Hagel’s confirmation hearing.

“I am concerned about some of his statements on Iran and Hamas and Israel,” said Collins. “I’m sure that those issues will be explored in the nomination hearing, should he be nominated.”

“Chuck’s going to get asked some very tough questions, but Chuck’s a big boy and he knows what he is getting into,” said another Armed Services panelist, Sen. Saxby Chambliss, R-Ga.

Chambliss also noted that Hagel “was a very popular person here.”

It would be difficult for Republicans to block a nominee who for more than a decade was a leading voice in their own party. Though he broke with the GOP and then-President George W. Bush on the Iraq war, voting in 2007 to withdraw all troops from the country, he consistently voted with the Bush White House on a host of other issues.

McCain indicated Thursday that in addition to his statements on Israel — including one suggesting that “the Jewish lobby intimidates a lot of people” on Capitol Hill — Hagel’s past opposition to the 2007 “surge” of troops Bush sent into Iraq would be a factor in his considerations, should Hagel be nominated.

Added McCain, “To allege that he is somehow a Republican, that’s a hard one to swallow.”

In fact, Hagel voted with his party at a higher rate than McCain did over the time the two men served together in the Senate.

Hagel has, however, eased closer toward Democratic positions since retiring from the Senate, calling for a smaller footprint in Afghanistan, for example, and forging a relationship with Obama as a co-chairman of the president’s Intelligence Advisory Board.

After already tussling with the Obama administration on one not-yet-nominee, Republicans may also be calculating that they would be overplaying their hand to try and block another pick before a nomination has been formally announced.

“Out of respect to the president, I’m not going to comment on his hypothetical appointments,” Sen. Lamar Alexander, R-Tenn., said Tuesday when asked about Hagel’s qualifications to head up the Pentagon. “I’m going to wait and see who the president nominates and then carefully consider someone, especially for that position.”